svn commit: r360727 - stable/11/sys/netinet

[Michael Tuexen]

Author: tuexen
Date: Thu May  7 00:50:50 2020
New Revision: 360727
URL: https://svnweb.freebsd.org/changeset/base/360727

Log:
  MFC r350626: Fix a locking issue in SCTP
  
  Fix a locking issue in sctp_accept.
  
  PR:		238520
  Reported by:	pho

Modified:
  stable/11/sys/netinet/sctp_usrreq.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/netinet/sctp_usrreq.c
==============================================================================
--- stable/11/sys/netinet/sctp_usrreq.c	Thu May  7 00:44:15 2020	(r360726)
+++ stable/11/sys/netinet/sctp_usrreq.c	Thu May  7 00:50:50 2020	(r360727)
@@ -7229,28 +7229,56 @@ sctp_accept(struct socket *so, struct sockaddr **addr)
 		SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_USRREQ, EINVAL);
 		return (ECONNRESET);
 	}
-	SCTP_INP_RLOCK(inp);
+	SCTP_INP_WLOCK(inp);
 	if (inp->sctp_flags & SCTP_PCB_FLAGS_UDPTYPE) {
-		SCTP_INP_RUNLOCK(inp);
+		SCTP_INP_WUNLOCK(inp);
 		SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_USRREQ, EOPNOTSUPP);
 		return (EOPNOTSUPP);
 	}
 	if (so->so_state & SS_ISDISCONNECTED) {
-		SCTP_INP_RUNLOCK(inp);
+		SCTP_INP_WUNLOCK(inp);
 		SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_USRREQ, ECONNABORTED);
 		return (ECONNABORTED);
 	}
 	stcb = LIST_FIRST(&inp->sctp_asoc_list);
 	if (stcb == NULL) {
-		SCTP_INP_RUNLOCK(inp);
+		SCTP_INP_WUNLOCK(inp);
 		SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP_USRREQ, EINVAL);
 		return (ECONNRESET);
 	}
 	SCTP_TCB_LOCK(stcb);
-	SCTP_INP_RUNLOCK(inp);
 	store = stcb->asoc.primary_destination->ro._l_addr;
 	SCTP_CLEAR_SUBSTATE(stcb, SCTP_STATE_IN_ACCEPT_QUEUE);
-	SCTP_TCB_UNLOCK(stcb);
+	/* Wake any delayed sleep action */
+	if (inp->sctp_flags & SCTP_PCB_FLAGS_DONT_WAKE) {
+		inp->sctp_flags &= ~SCTP_PCB_FLAGS_DONT_WAKE;
+		if (inp->sctp_flags & SCTP_PCB_FLAGS_WAKEOUTPUT) {
+			inp->sctp_flags &= ~SCTP_PCB_FLAGS_WAKEOUTPUT;
+			SOCKBUF_LOCK(&inp->sctp_socket->so_snd);
+			if (sowriteable(inp->sctp_socket)) {
+				sowwakeup_locked(inp->sctp_socket);
+			} else {
+				SOCKBUF_UNLOCK(&inp->sctp_socket->so_snd);
+			}
+		}
+		if (inp->sctp_flags & SCTP_PCB_FLAGS_WAKEINPUT) {
+			inp->sctp_flags &= ~SCTP_PCB_FLAGS_WAKEINPUT;
+			SOCKBUF_LOCK(&inp->sctp_socket->so_rcv);
+			if (soreadable(inp->sctp_socket)) {
+				sctp_defered_wakeup_cnt++;
+				sorwakeup_locked(inp->sctp_socket);
+			} else {
+				SOCKBUF_UNLOCK(&inp->sctp_socket->so_rcv);
+			}
+		}
+	}
+	SCTP_INP_WUNLOCK(inp);
+	if (stcb->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED) {
+		sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
+		    SCTP_FROM_SCTP_USRREQ + SCTP_LOC_19);
+	} else {
+		SCTP_TCB_UNLOCK(stcb);
+	}
 	switch (store.sa.sa_family) {
 #ifdef INET
 	case AF_INET:
@@ -7291,40 +7319,6 @@ sctp_accept(struct socket *so, struct sockaddr **addr)
 	default:
 		/* TSNH */
 		break;
-	}
-	/* Wake any delayed sleep action */
-	if (inp->sctp_flags & SCTP_PCB_FLAGS_DONT_WAKE) {
-		SCTP_INP_WLOCK(inp);
-		inp->sctp_flags &= ~SCTP_PCB_FLAGS_DONT_WAKE;
-		if (inp->sctp_flags & SCTP_PCB_FLAGS_WAKEOUTPUT) {
-			inp->sctp_flags &= ~SCTP_PCB_FLAGS_WAKEOUTPUT;
-			SCTP_INP_WUNLOCK(inp);
-			SOCKBUF_LOCK(&inp->sctp_socket->so_snd);
-			if (sowriteable(inp->sctp_socket)) {
-				sowwakeup_locked(inp->sctp_socket);
-			} else {
-				SOCKBUF_UNLOCK(&inp->sctp_socket->so_snd);
-			}
-			SCTP_INP_WLOCK(inp);
-		}
-		if (inp->sctp_flags & SCTP_PCB_FLAGS_WAKEINPUT) {
-			inp->sctp_flags &= ~SCTP_PCB_FLAGS_WAKEINPUT;
-			SCTP_INP_WUNLOCK(inp);
-			SOCKBUF_LOCK(&inp->sctp_socket->so_rcv);
-			if (soreadable(inp->sctp_socket)) {
-				sctp_defered_wakeup_cnt++;
-				sorwakeup_locked(inp->sctp_socket);
-			} else {
-				SOCKBUF_UNLOCK(&inp->sctp_socket->so_rcv);
-			}
-			SCTP_INP_WLOCK(inp);
-		}
-		SCTP_INP_WUNLOCK(inp);
-	}
-	if (stcb->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED) {
-		SCTP_TCB_LOCK(stcb);
-		sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
-		    SCTP_FROM_SCTP_USRREQ + SCTP_LOC_19);
 	}
 	return (0);
 }